add missing codes for flow and bottomsheet

Author: zhuxingwei

Samples/UIWidgetsSamples_2019_4/Assets/MaterialSample/FlowSample.cs

@@ -0,0 +1,162 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using uiwidgets;
+using Unity.UIWidgets.animation;
+using Unity.UIWidgets.engine;
+using Unity.UIWidgets.foundation;
+using Unity.UIWidgets.material;
+using Unity.UIWidgets.painting;
+using Unity.UIWidgets.rendering;
+using Unity.UIWidgets.ui;
+using Unity.UIWidgets.widgets;
+using ui_ = Unity.UIWidgets.widgets.ui_;
+
+namespace UIWidgetsSample
+{
+    public class FlowSample : UIWidgetsPanel
+    {
+        protected override void main()
+        {
+            ui_.runApp(new MaterialApp(
+                showPerformanceOverlay: false,
+                home: new FlowDemo()));
+        }
+
+        protected new void OnEnable()
+        {
+            base.OnEnable();
+        }
+        
+        protected override void onEnable()
+        {
+            AddFont("Material Icons", new List<string> {"MaterialIcons-Regular.ttf"}, new List<int> {0});
+        }
+    }
+
+    public class FlowDemo : StatefulWidget
+    {
+        public FlowDemo(Key key = null) : base(key)
+        {
+        }
+
+        public override State createState()
+        {
+            return new _FlowDemoState();
+        }
+    }
+
+    class FlowDemoDelegate : FlowDelegate
+    {
+        public FlowDemoDelegate(Animation<float> myAnimation) : base(repaint: myAnimation)
+        {
+            this.myAnimation = myAnimation;
+        }
+
+        Animation<float> myAnimation;
+
+        public override bool shouldRepaint(FlowDelegate oldDelegate)
+        {
+            var _oldDelegate = oldDelegate as FlowDemoDelegate;
+            return myAnimation != _oldDelegate?.myAnimation;
+        }
+
+        public override void paintChildren(FlowPaintingContext context)
+        {
+            for (int i = context.childCount - 1; i >= 0; i--)
+            {
+                float dx = (context.getChildSize(i).height + 10) * i;
+                context.paintChild(
+                    i,
+                    transform: Matrix4.translationValues(0, dx * myAnimation.value + 10, 0)
+                );
+            }
+        }
+
+        public override Size getSize(BoxConstraints constraints)
+        {
+            return new Size(70.0f, float.PositiveInfinity);
+        }
+
+
+        public override BoxConstraints getConstraintsForChild(int i, BoxConstraints constraints)
+        {
+            return i == 0 ? constraints : BoxConstraints.tight(new Size(50.0f, 50.0f));
+        }
+    }
+
+    public class _FlowDemoState : SingleTickerProviderStateMixin<FlowDemo>
+    {
+        private AnimationController _myAnimation;
+
+        List<IconData> _icons = new List<IconData>
+        {
+            Icons.menu,
+            Icons.email,
+            Icons.settings,
+            Icons.notifications,
+            Icons.person,
+            Icons.wifi
+        };
+
+        public override void initState()
+        {
+            base.initState();
+
+            _myAnimation = new AnimationController(
+                duration: new TimeSpan(0, 0, 0, 1),
+                vsync: this
+            );
+        }
+
+        Widget _buildItem(IconData icon)
+        {
+            return new Padding(
+                padding: EdgeInsets.symmetric(horizontal: 10.0f),
+                child: new RawMaterialButton(
+                    fillColor: Colors.cyan,
+                    shape: new CircleBorder(),
+                    constraints: BoxConstraints.tight(Size.square(50.0f)),
+                    onPressed: () =>
+                    {
+                        if (_myAnimation.status == AnimationStatus.completed)
+                        {
+                            _myAnimation.reverse();
+                        }
+                        else
+                        {
+                            _myAnimation.forward();
+                        }
+                    },
+                    child: new Icon(
+                        icon,
+                        color: Colors.white,
+                        size: 30.0f
+                    )
+                )
+            );
+        }
+
+        public override Widget build(BuildContext context)
+        {
+            return new Scaffold(
+                appBar: new AppBar(
+                    automaticallyImplyLeading: false,
+                    title: new Text("Flutter Flow Widget Demo"),
+                    backgroundColor: Colors.cyan
+                ),
+                body: new Stack(
+                    children: new List<Widget>
+                    {
+                        new Container(color: Colors.grey[200]),
+                        new Flow(
+                            _delegate: new FlowDemoDelegate(myAnimation: _myAnimation),
+                            children: _icons
+                                .Select((IconData icon) => _buildItem(icon)).ToList()
+                        ),
+                    }
+                )
+            );
+        }
+    }
+}

Samples/UIWidgetsSamples_2019_4/Assets/MaterialSample/FlowSample.cs.meta

@@ -76,13 +76,11 @@ public static PersistentBottomSheetController<object> showBottomSheet(
             D.assert(builder != null);
             D.assert(debugCheckHasScaffold(context));
             return Scaffold.of(context).showBottomSheet(
-                builder
-                //TODO: update showBottomSheet
-                // ,
-                // backgroundColor: backgroundColor,
-                // elevation: elevation,
-                // shape: shape,
-                // clipBehavior: clipBehavior
+                builder,
+                backgroundColor: backgroundColor,
+                elevation: elevation,
+                shape: shape,
+                clipBehavior: clipBehavior
             );
         }
     }
@@ -111,6 +109,11 @@ public BottomSheet(
             this.elevation = elevation;
             this.onClosing = onClosing;
             this.builder = builder;
+            this.onDragStart = onDragStart;
+            this.onDragEnd = onDragEnd;
+            this.backgroundColor = backgroundColor;
+            this.shape = shape;
+            this.clipBehavior = clipBehavior;
         }
 
         public readonly AnimationController animationController;